Drug development continues to be a major endeavor in the pharmaceutical industry. Drug development requires clinical trials to establish the safety and efficacy of new treatments. Today, in the United States, alone, there are a large number of on-going clinical trials in various stages. Each clinical trial can involve hundreds to thousands of patients who have volunteered to the administering of certain experimental drugs. Generally speaking, as part of the clinical trial, biological samples (e.g., tissue, urine, blood samples) are collected from participants at a clinical site, such as a hospital, university, or physician office, and then transported to laboratories for analysis or to facilities where they may be stored frozen for analysis at a later time.
The ability to evaluate the safety and efficacy of an experimental drug requires obtaining reproducible and reliable results during the clinical trials. The biological samples must be stabilized and preserved during storage and transport between, by way of example, the clinic and the laboratory. A common means to preserve biological samples today is to freeze and store them in the presence of solid carbon dioxide (i.e., dry ice).
Dry ice systems typically involve manually loading the samples and dry ice into an insulated box, such as a polystyrene box, at the clinical site where the samples are acquired. The insulated box is typically provided to the clinical site by a pharmaceutical company or contract research organization administering the clinical trial. The insulated box components may be provided in an assembled or disassembled state. Assembly of the insulated box and loading of the dry ice can be labor intensive. There may also be considerable cost and inconvenience associated with maintaining a sufficient supply of dry ice at the clinical site. Additionally, the failure to use such dry ice within a certain duration can cause the dry ice to lose its cooling effect. Further, the insulated box is typically not reusable and must be discarded, thereby creating waste.
Other drawbacks also exist with the transport of samples in conventional insulated boxes. The dry ice cools the interior of the insulated box as it sublimates to carbon dioxide vapor. A number of insulated boxes are available that can maintain a cold interior temperature for various durations up to four or five days. The interior sample space may be uniformly near dry ice temperature upon initial full dry ice loading, but as the dry ice sublimates, significant temperature gradients can arise within the interior sample space, potentially compromising sample quality. The insulated boxes are generally shipped via expedited delivery methods to ensure a sufficiently cold temperature is maintained within the interior sample space. However, should delays or disruptions occur in the shipping lanes, the samples can degrade. As a result of such delays during shipment, additional dry ice may be required to be loaded into the box during transit, which results in increased cost and logistical complexity to the shipment.
One alternative to conventional dry ice shippers is a cryogenic liquid nitrogen-based vapor vessels. Cryogenic liquid nitrogen-based vapor vessels utilize an absorbent to retain the cold nitrogen in the vapor state and avoid the presence of nitrogen in its liquid form. However, such liquid nitrogen-based vapor vessels suffer from drawbacks. One drawback is the time and labor involved in the preparation of the vessel. Specifically, users prepare such vessels by pouring liquid nitrogen into the vessel; waiting several hours to allow for sufficient absorption of the nitrogen onto the absorbent to occur; followed by decanting the excess liquid nitrogen prior to shipment. Substantial handling of the cryogenic liquid nitrogen is necessary, and significant time is required to prepare the liquid nitrogen shipper prior to its usage. Further, the costs associated with the use of liquid nitrogen-based vapor vessels are significantly higher than alternative dry ice vessels.
In view of these drawbacks, there is an unmet need for an improved way for preserving samples into a container during storage and transport.